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how much fuel is required?

cub124

cub124

Half Moon Detroit #1
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Location
stormstown PA
Does anyone have a spec on the maximum fuel required in gph for the 4911 pump, or any of them for that matter? Also willing to see formulas for calculating max fuel consumption per hour.

I'm just looking to update my fuel pump sometime and don't want to waste the money over doing it too much nor do I wanna under do it. I would like to know the spec or calculate it to find the GPH needed for a lift pump @ lets say 350-400hp flywheel when realistically I'll be lucky to see 300 flywheel.
 
For 400HP you need to plan on about 50GPH at 7 PSI. In a diesel powered IDI like the 6.5 you will only be running about 38-40 GPH through the engine, but will need an excess to handle returned fuel from the injectors and pump. A good way to figure fuel needed is to take your HP and divide it by 10, this will give you roughly how much fuel you would need for a gasoline powered engine. Then take that number and multiply it by 80-90%(this number will vary depending on the technology of the engine. For an IDI it will be closer to 85-90% at WOT where a DI diesel will be in the 75-80% range at WOT. Also the higher the HP goes beyond the 1:1 ratio of HP to CI, the less efficient and higher the fuel burn will be.) to get the diesel burn, then add in about 20% to make up for returned fuel.
 
alright thanks, Im pushing fuel through two filters a 12 and 2 micron. I should probably invest in a gauge after the filters and put it in the cab so I can see if I hit 0psi under WOT (which I probably do)
 
I know they are more of a tuning tool than exact measurements but I did manage to hit at one time 274RWHP with a stock lift pump and no Feed The Beast mod on the dyno. I have to hand the stocker some credit. I am gonna get a small refund from my college soon. I am gonna try to get a FRB5. I just hope it will really pick my top end up.
 
For some reason I thought I had my gauge before the filters but it was already after so I just ran a line into the cab so I could watch the fuel pressure and sure enough cursing in 4th gear around 50-60 mph on flat it stays around 2psi and at WOT the gauge pins to 0 psi.

The only odd thing is that if I stomp on it in 2nd gear and run the gear out till the end @ WOT the whole time my truck will blow tons of smoke when it gets into the higher rmps with about 15 psi of boost. The only reasoning I can find for this is that the engine is not burning the fuel as efficiently as it does at lower rmps but the IP must be pulling enough fuel.

With this info I doubt I will feel a huge gain in power but maybe my spool time will decrease by fractions of a second. I guess Ill wait and see :hihi:

as for the pump I'm going with the Holley blue 110 gph at 14psi so I shouldn't need a regulator and they can be found used at a cheap price!
 
I have one on a gasser (old 70 Chevy) I'll say its loud and being a rotor/vane type pump is probably not a FOF type pump?? Cheapest one I found in a search was $127
If you wind up going with the Holley my LP bypass fittings will still work with it also.

Holley Blue specs:
Features•Tumble polished billet look
• New lower housing casting for enhanced fuel flow
• Motor draws only 3 amps current
• 7 1/2 amp fuse recommended
• Improved design for street/strip applications
• Distinctive “BLUE” logo
• Flows 110 GPH (free flow)
• Flows 88 GPH at 9 PSI
• Maximum pressure is 14 PSI
• Includes P/N 12-803 fuel pressure regulator
• Provides constant fuel flow with no pulsation
• Has externally accessible pressure relief valve (max 14 PSI)
• Rotor/Vane pump design is more tolerant of contaminated fuels
• Weighs only 3 lbs
• Includes mounting bracket
• Repair kits are readily available
• Can be serviced from the pump end
• NOT compatible with alcohol or methanol fuels
• Use of safety shut-off switch, P/N 12-810, strongly recommended
• Not designed or recommended for use with fuel injection systems
 
Burning oil said:
Walbro FRB5 is a great choice, sold 2 today. http://wem.walbro.com/distributors/FR/FRB-5.htm
I sell them @ $145. not on my web site so PM me or email if I can help.
Click to expand...

I have tried about every lift pump out there. A noisy Carter rotory vane pump, Walbro in both flavors, Mallory 240GPH gerorator, factory and other stock type pumps...

Factory stuff is simply junk.

The longest life so far both age and miles is the FRB5 on the DB2 IP. I even had to rebuild it due to the bugs in diesel fuel issues I had. The other higher pressure Walbro didn't have parts available so I scrapped it.

So for the money and forget about it life I would recommend the Walbro by far over everything else. Everything else didn't even make 6 months for me.
 
WarWagon said:
I have tried about every lift pump out there. A noisy Carter rotory vane pump, Walbro in both flavors, Mallory 240GPH gerorator, factory and other stock type pumps...

Factory stuff is simply junk.

The longest life so far both age and miles is the FRB5 on the DB2 IP. I even had to rebuild it due to the bugs in diesel fuel issues I had. The other higher pressure Walbro didn't have parts available so I scrapped it.

So for the money and forget about it life I would recommend the Walbro by far over everything else. Everything else didn't even make 6 months for me.
Click to expand...

Yep and if someone can break it, War Wagon can :)
 
6.2 turbo did you route a LP bypass? I almost bought a holley blue last night for under 20 dollars + shipping but then I was reminded how noisy they can be. A friend of mine has one. If I wasn't such a tight wad Id probably buy the FRB5 and be done with it but I'll more than likely end up going with the Holley blue and try to quiet it down a bit, the engines already loud eh?
Thanks for everyone's 0.2¢
 
Holly Blue can be real quiet real sudden like. Because if it quits the engine suddenly dies like dropping the stop solenoid. Flow on fail is a big plus for the Walbro. What middle of nowhere snowbank you want to change a pump in? The damn thing ALWAYS fail in the middle of nowhere in bad weather.

The rotary vane pumps also tend to put small air bubbles in the fuel or at least the carter did for me.
 
Also the HOLLEY pump seals don't like diesel very much. PPE's pump used to be a rebadged HOLLEY black pump, but they had so many warranty problems they changed teh design a few years back.
 
I'm trying to correct some cavitation issues,which make the pump even louder. I never had a Holley pump stop running,so it has no bypass.
 
6.2 turbo said:
I'm trying to correct some cavitation issues,which make the pump even louder. I never had a Holley pump stop running,so it has no bypass.
Click to expand...

I have, and it's no fun. I lost a few of them in my race car years back. No fun to lose power mid track because your pump quit.
 
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